U.S. patent number 7,284,916 [Application Number 11/151,900] was granted by the patent office on 2007-10-23 for dual stage modular optical devices with insert digital diagnostics component.
This patent grant is currently assigned to Finisar Corporation. Invention is credited to Gary Sasser, Chris K. Togami.
United States Patent |
7,284,916 |
Sasser , et al. |
October 23, 2007 |
**Please see images for:
( Certificate of Correction ) ** |
Dual stage modular optical devices with insert digital diagnostics
component
Abstract
Embodiments of the present invention are directed to dual stage
modular optical devices with insert digital diagnostics components.
A first portion of a leadframe couples a first fabricated package
including a light source and/or light detector to a second
fabricated package with first opening for receiving inserts. A
second portion of the leadframe couples the second fabricated
package to a third fabricated package with a second opening for
receiving inserts. A first component insert is coupled to the
second fabricated package such that components of the first
component insert can electrically interoperate with the light
source and/or light detector. A second component insert is coupled
to the third fabricated package such that components of the second
component insert can electrically interoperate with components of
the first component insert to implement digital diagnostics
functions.
Inventors: |
Sasser; Gary (San Jose, CA),
Togami; Chris K. (San Jose, CA) |
Assignee: |
Finisar Corporation (Sunnyvale,
CA)
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Family
ID: |
35504752 |
Appl.
No.: |
11/151,900 |
Filed: |
June 13, 2005 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20050285236 A1 |
Dec 29, 2005 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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60579121 |
Jun 11, 2004 |
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Current U.S.
Class: |
385/92; 385/93;
398/135; 398/140; 398/161; 398/164 |
Current CPC
Class: |
G02B
6/4204 (20130101); G02B 6/423 (20130101); G02B
6/4292 (20130101); H01L 2924/0002 (20130101); H01L
2924/0002 (20130101); H01L 2924/00 (20130101) |
Current International
Class: |
G02B
6/36 (20060101); H04B 10/00 (20060101) |
Field of
Search: |
;398/128,130,135,138-141,164 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Connelly-Cushwa; Michelle
Assistant Examiner: Chu; Chris
Attorney, Agent or Firm: Workman Nydegger
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
The present invention claims priority to U.S. Provisional patent
application Ser. No. 60/579,121, entitled "Dual Stage Modular
Optical Devices With Insert Digital Diagnostics Components", filed
on Jun. 11, 2004, the entire contents of which are incorporated
herein by reference.
Claims
What is claimed and desired secured by United States Letters Patent
is:
1. An modular optical device, comprising: a first fabricated
package including at least one of a light source for generating
optical signals and a light detector for detecting received optical
signals; a second fabricated package with a first opening for
receiving component inserts; a first leadframe portion that
mechanically connects the first fabricated package to the second
fabricated package and that electrically connects the at least one
of the light source and light detector in the first fabricated
package to first contacts of the first leadframe portion exposed in
the first opening; a first component insert mechanically coupled to
the second fabricated package and electrically coupled to the
exposed first contacts such that components of the first component
insert can electrically interoperate with the at least one of the
light source and light detector; a third fabricated package with a
second opening for receiving component inserts; a second leadframe
portion that mechanically connects the second fabricated package to
the third fabricated package and electrically connects the first
exposed contacts to second contacts of the second leadframe portion
exposed in the second opening; and a second component insert
mechanically coupled to the third fabricated package and
electrically coupled to the exposed second contacts such that
components of the second component insert can electrically
interoperate with components of the first component insert to
implement digital diagnostics functions.
2. The modular optical device as recited in claim 1, wherein the
first fabricated package includes a light detector for detecting
optical signals.
3. The modular optical device as recited in claim 1, further
comprising: a third leadframe portion mechanically and electrically
connected to the second exposed contacts, the third lead fame
portion facilitating mechanical and/or electrical connections
between the modular optical device and external components.
4. The modular optical device as recited in claim 1, further
comprising a lens block mechanically coupled to the first
fabricated package, the lens block configured such that one or more
lens pins can mechanically couple to the lens block.
5. The modular optical device as recited in claim 4, further
comprising: a lens pin mechanically coupled to the lens block, the
lens pin for directing an optical signal between a light source and
corresponding external component.
6. The modular optical device as recited in claim 4, further
comprising: a lens pin mechanically coupled to the lens block, the
lens pin for directing an optical signal between an external
component and a corresponding light detector.
7. The modular optical device as recited in claim 1, wherein the
first fabricated package includes a laser.
8. The modular optical device as recited in claim 7, wherein the
first fabricated package includes a vertical cavity surface
emitting laser.
9. The modular optical device as recited in claim 1, wherein the
first fabricated package includes a photodiode.
10. The modular optical device as recited in claim 1, wherein the
first fabricated package is a plastic fabricated package, the
second fabricated package is a plastic fabricated package, and the
third fabricated package is a plastic fabricated package.
11. The modular optical device as recited in claim 1, wherein the
first component insert includes a laser driver circuit.
12. The modular optical device as recited in claim 1, wherein the
first component insert includes a transimpedance amplifier
circuit.
13. The modular optical device as recited in claim 1, wherein
contacts of the first component insert are wired bonded to the
first exposed contacts.
14. The modular optical device as recited in claim 1, wherein the
first component insert is mechanically coupled to the second
fabricated package with epoxy.
15. The modular optical device as recited in claim 1, wherein the
first component insert includes one or more integrated circuits
that are die attached and wire bonded to the component insert.
16. The modular optical device as recited in claim 1, wherein the
first component insert includes one or more surface mount
components that are surface mounted on the first component
insert.
17. The modular optical device as recited in claim 1, wherein the
second component insert includes components for implementing
digital diagnostics functions.
18. The modular optical device as recited in claim 17, wherein
components of the second component insert are configured to
interoperate with components of the first component insert to
implement one or more of: providing diagnostic information about a
modular optical device's operating conditions, generating
diagnostic data by digitizing analog modular optical device
signals, internally calibrating the modular optical device,
externally calibrating the modular optical device, issuing alarms,
issuing warnings, retrieving vendor information, and querying the
modular optical device for supported features.
19. The modular optical device as recited in claim 1, wherein the
second component insert includes a processor.
20. The modular optical device as recited in claim 1, wherein the
second component insert includes memory.
21. The modular optical device as recited in claim 1, wherein
contacts of the second component insert are wired bonded to the
second exposed contacts.
22. The modular optical device as recited in claim 1, wherein the
second component insert is mechanically coupled to the third
fabricated package with epoxy.
23. The modular optical device as recited in claim 1, wherein the
second component insert includes one or more integrated circuits
that are die attached and wire bonded to the second component
insert.
24. The modular optical device as recited in claim 1, wherein the
second component insert includes one or more surface mount
components that are surface mounted on the second component
insert.
25. The modular optical device as recited in claim 1, further
comprising: an external housing having dimensions in accordance
with a small form factor pluggable form factor, the external
housing surrounding the first fabricated package, the second
fabricated package, the first leadframe portion, the first
component insert, the third fabricated package, the second
leadframe portion, and the second component insert.
26. The modular optical device as recited in claim 1, further
comprising: at least one other fabricated package; and additional
leadframe portions that mechanically connect the at least one other
fabricated package to the third fabricated package.
27. An optoelectronic interface device comprising: a host bus
adapter having a printed circuit board with at least one connector
for electrically interfacing with a host device; and a modular
optical device configured to mechanically and electrically
interface with the host bus adapter, the modular optical device
comprising: a first fabricated package including at least one of a
light source and a light detector; a second fabricated package with
a first opening for receiving component inserts that are to
electrically interoperate with the at least one of a light source
and a light detector; a first leadframe portion that mechanically
connects the first fabricated package to the second fabricated
package and that electrically connects the at least one of a light
source and light detector to first contacts of the first leadframe
portion exposed in the first opening; a first component insert
mechanically coupled to the second fabricated package and
electrically coupled to the first exposed contacts such that
components of the first component insert can electrically
interoperate with components included in the first fabricated
package to transfer optical signals; a third fabricated package
with a second opening for receiving component inserts, the third
fabricated package including a third leadframe portion for
connecting the modular optical device to the host bus adapter; a
second leadframe portion that mechanically connects the third
fabricated package to the second fabricated package and
electrically connects the first exposed contacts to second contacts
of the second leadframe portion exposed in the second opening; and
a second component insert mechanically coupled to the third
fabricated package and electrically coupled to the exposed second
contacts such that components of the second component insert can
electrically interoperate with components of the first component
insert to implement digital diagnostics functions; a lens block
mechanically coupled to the first fabricated package, the lens
block configured to receive one or more lens pins; and at least one
lens pin mechanically coupled to the lens block, the at least one
lens pin for transferring an optical signal between the at least
one of a light source and a light detector and an external
component.
28. The optoelectronic interface device as recited in claim 27,
wherein the optoelectronic interface device is configured to be
substantially received within a standard slot of the host
device.
29. The optoelectronic interface device as recited in claim 28,
wherein the standard slot comprises one of: a PCI card slot and a
PCMCIA card slot.
30. The optoelectronic interface device as recited in claim 27,
wherein the host bus adapter comprises a printed circuit board for
one of: a peripheral component interconnect card and a PCMCIA
card.
31. The optoelectronic interface device as recited in claim 27,
wherein the first component insert is a laser driver PCB
insert.
32. The optoelectronic interface device as recited in claim 27,
wherein the second component insert is a digital diagnostics PCB
insert.
33. The optoelectronic interface device as recited in claim 27,
wherein components of second component insert are configured to
interoperate with components of the first component insert to
implement one or more of: providing diagnostic information about a
modular optical device's operating conditions, generating
diagnostic data by digitizing analog modular optical device
signals, internally calibrating a modular optical device,
externally calibrating a modular optical device, issuing alarms,
issuing warnings, retrieving vendor information, and querying the
modular optical device for supported features.
34. The optoelectronic interface device as recited in claim 27,
wherein the second component insert includes a processor.
35. The optoelectronic interface device as recited in claim 27,
wherein the second component insert includes memory.
36. A modular optical device comprising: a first fabricated package
including a laser and a photodiode; a second fabricated package
with a first opening for receiving component inserts; a first
leadframe portion that mechanically connects the first fabricated
package to the second fabricated package and that electrically
connects the laser and the photodiode to first contacts of the
first leadframe portion exposed in the first opening; a driver
component insert mechanically coupled to the second fabricated
package and electrically coupled to the exposed first contacts such
that components included in the driver component insert can
electrically interoperate with the laser and photodiode; a digital
diagnostics insert fabricated package with a second opening for
receiving component inserts; a second leadframe portion that
mechanically connects the third fabricated package to the second
fabricated package and electrically connects the first exposed
contacts to second contacts of the second fabricated package
exposed in the second opening; a digital diagnostics component
insert mechanically coupled to the third fabricated package and
electrically coupled to the exposed second contacts such that
components of the digital diagnostics insert can electrically
interoperate with components of the driver component insert to
implement digital diagnostics functions; a lens block mechanically
coupled to the first fabricated package and configured to receive a
plurality of lens pins; a first lens pin mechanically coupled to
the lens block for directing an optical signal from the laser to an
external component; and a second lens pin mechanically coupled to
the lens block for directing an optical signal from an external
component to the photodiode.
37. The modular optical device recited in claim 36, wherein the
laser is a vertical cavity surface emitting laser.
Description
BACKGROUND OF THE INVENTION
1. The Field of the Invention
The present invention is generally related to optical devices used
in fiber optic communications systems. More particularly, the
present invention provides for dual stage modular optical devices
with insert digital diagnostics components.
2. The Relevant Technology
Fiber optic technology is increasingly employed as a method by
which information can be reliably transmitted via a communications
network. Networks employing fiber optic technology are known as
optical communications networks, and are marked by high bandwidth
and reliable, high-speed data transmission.
Optical communications networks employ optical transceivers in
transmitting information via the network from a transmission node
to a reception node. Generally, such optical transceivers implement
both data signal transmission and reception capabilities. For
example, a transmitter portion of a transceiver is configured to
convert an incoming electrical data signal into an optical data
signal and a receiver portion of the transceiver is configured to
convert an incoming optical data signal into an electrical data
signal.
More particularly, an optical transceiver at the transmission node
receives an electrical data signal from a network device, such as a
computer, and converts the electrical data signal to a modulated
optical data signal using an optical transmitter such as a laser.
The optical data signal can then be transmitted in a fiber optic
cable via the optical communications network to a reception node of
the network. At the reception node, the optical data signal is
received at another optical transceiver that uses a photodetector,
such as a photodiode, to convert the received optical data signal
back into an electrical data signal. The electrical data signal is
then forwarded to a host device, such as a computer, for
processing.
Generally, multiple components are designed to accomplish different
aspects of these functions. For example, an optical transceiver can
include one or more optical subassemblies ("OSA") such as a
transmit optical subassembly ("TOSA"), and a receive optical
subassembly ("ROSA"). Typically, each OSA is created as a separate
physical entity, such as a hermetically sealed cylinder that
includes one or more optical sending or receiving components, as
well as electrical circuitry for handling and converting between
optical and electrical signals. Within the optical transceiver,
each OSA generally includes electrical connections to various
additional components such as a transceiver substrate, sometimes
embodied in the form of a printed circuit board ("PCB"). OSAs in a
conventional transceiver are generally oriented such that a
longitudinal axis defined by the OSA is substantially parallel to
the transceiver substrate. The transceiver substrate, in turn, is
mounted to the board of a host bus adapter ("HBA") or other
component.
The transceiver substrate can include multiple other active
circuitry components particularly designed to drive or handle
electrical signals sent to or returning from one or more of the
OSAs. Accordingly, such a transceiver substrate will usually
include a number of electrical transmission lines with the one or
more OSAs. Such connections may include "send" and "receive" data
transmission lines for each OSA, one or more power transmission
lines for each OSA, and one or more diagnostic data transmission
lines for each OSA. These transmission lines are connected between
the transceiver substrate and the OSA using different types of
electrical connectors, examples of which include an electrical flex
circuit, a direct mounting connection between conductive metallic
pins extending from the OSA and solder points on the PCB, and a
plug connection that extends from the PCB and mounts into
electrical extensions from an OSA.
As part of ongoing efforts to uniformly reduce the size of optical
transceivers and other components, manufacturing standards such as
the small form factor ("SFF"), small form factor pluggable ("SFP"),
and 10 gigabit small form factor pluggable ("XFP") standards have
been developed. Nonetheless, the size of most optical transceivers,
even those that comply with such manufacturing standards, best
suits them for external connections to a computer system, such as a
desktop computer, a laptop computer, or a handheld digital
device.
For example, an SFF or SFP optical transceiver can be used to
provide an interface between an optical cable and a standard
network cable, such as an Ethernet cable for example, that plugs
into a computer system. Alternatively, a number of optical
transceivers can be mounted in a network panel and configured to
include an external connection to a computer system. However, the
number of components within a conventional transceiver, as well as
the orientation and the size of SFF or SFP optical transceivers,
makes it difficult, if not impossible, to integrate conventional
optical transceivers into smaller spaces, such as within a
pluggable card for use in a laptop computer or hand held device.
For example, despite their relatively compact nature, conventional
SFF, SFP, and XFP optical transceiver bodies are still too wide
and/or tall to fit within a typical PCMCIA laptop envelope.
A related problem concerns the connections of the optical
transceiver. In particular, use of the optical transceiver as an
external, rather than internal, component necessitates the use of
additional connectors and connections, which increase both the
overall cost associated with the system as well as the complexity
of the system. As well, optical transceivers employed in an
external, rather than integrated, configuration are more prone to
rough handling and damage than an integrated component.
Furthermore, even if the conventional optical transceiver could fit
within such an envelope, the length of the conventional SFF, SFP,
or XFP optical transceiver is such that the transceiver substrate
takes up an inordinate amount of board space on a corresponding
host bus adapter ("HBA") or other component to which the optical
transceiver is attached. This problem is of particular concern in
light of the concurrent demands for increases in functionality and
decreases in component size. These, and other, considerations make
conventional optical transceivers less than ideal for integration
within many computer systems. Accordingly, what would be
advantageous are reduced cost optical transceivers that can fit
within relatively small envelopes such that the optical transceiver
can be integrated within compact components and various computing
systems and devices.
BRIEF SUMMARY OF THE INVENTION
The foregoing problems with the prior state of the art are overcome
by the principles of the present invention, which are directed to
dual stage modular optical devices with insert digital diagnostics
components. A first fabricated package includes at least one of a
light source for generating optical signals and a light detector
for detecting received optical signals. A second fabricated package
includes a first opening for receiving component inserts. A first
leadframe portion mechanically connects the first fabricated
package to the second fabricated package and electrically connects
the at least one of the light source and light detector in the
first fabricated package to first contacts of the first leadframe
portion exposed in the first opening. A first component insert is
mechanically coupled to the second fabricated package and
electrically coupled to the exposed first contacts such that
components of the first component insert can electrically
interoperate with the at least one of the light source and light
detector.
A third fabricated package includes a second opening for receiving
component inserts. A second leadframe portion mechanically connects
the second fabricated package to the third fabricated package and
electrically connects the first exposed contacts to second contacts
of the second leadframe portion exposed in the second opening. A
second component insert is mechanically coupled to the third
fabricated package and electrically coupled to the exposed second
contacts such that components of the second component insert can
electrically interoperate with components of the first component
insert to implement digital diagnostics functions.
Additional features and advantages of the invention will be set
forth in the description that follows, and in part will be obvious
from the description, or may be learned by the practice of the
invention. The features and advantages of the invention may be
realized and obtained by means of the instruments and combinations
particularly pointed out in the appended claims. These and other
features of the present invention will become more fully apparent
from the following description and appended claims, or may be
learned by the practice of the invention as set forth
hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to describe the manner in which the above-recited and
other advantages and features of the invention can be obtained, a
more particular description of the invention briefly described
above will be rendered by reference to specific embodiments thereof
which are illustrated in the appended drawings. Understanding that
these drawings depict only typical embodiments of the invention and
are not therefore to be considered to be limiting of its scope, the
invention will be described and explained with additional
specificity and detail through the use of the accompanying drawings
in which:
FIG. 1A illustrates an example leadframe including components of an
example dual stage fabricated package with digital diagnostics
insert package.
FIG. 1B illustrates components of the example dual stage fabricated
package with digital diagnostics insert package in a fully open
configuration relative to corresponding component inserts.
FIG. 2A illustrates an example dual stage fabricated package with
digital diagnostics insert package including corresponding
component inserts in a partially formed configuration relative to
other optical components.
FIG. 2B illustrates an example of an assembled modular optical
device including a dual stage fabricated package with digital
diagnostics insert package.
FIG. 2C illustrates an example of an assembled modular optical
device including a dual stage fabricated package with digital
diagnostics insert package in a fully formed configuration.
FIG. 3A illustrates an example side view of an assembled modular
optical device package including dual stage fabricated package with
digital diagnostics insert package coupled to a substrate.
FIG. 3B illustrates an example side view of an alternate
configuration of an assembled modular optical device package
including dual stage fabricated package with digital diagnostics
insert package coupled to a substrate.
FIG. 3C illustrates an example side view of another alternate
configuration of an assembled modular optical device package
including dual stage fabricated package with digital diagnostics
insert package coupled to a substrate.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The principles of the present invention relate to dual stage
modular optical devices with insert digital diagnostics components.
A first fabricated package includes at least one of a light source
for generating optical signals and a light detector for detecting
received optical signals. A second fabricated package includes a
first opening for receiving component inserts. A first leadframe
portion mechanically connects the first fabricated package to the
second fabricated package and electrically connects the at least
one of the light source and light detector in the first fabricated
package to first contacts of the first leadframe portion exposed in
the first opening. A first component insert is mechanically coupled
to the second fabricated package and electrically coupled to the
exposed first contacts such that components of the first component
insert can electrically interoperate with the at least one of the
light source and light detector.
A third fabricated package includes a second opening for receiving
component inserts. A second leadframe portion mechanically connects
the second fabricated package to the third fabricated package and
electrically connects the first exposed contacts to second contacts
of the second leadframe portion exposed in the second opening. A
second component insert is mechanically coupled to the third
fabricated package and electrically coupled to the exposed second
contacts such that components of the second component insert can
electrically interoperate with components of the first component
insert to implement digital diagnostics functions.
In general, embodiments of the present invention describe modular
optical devices (e.g., TOSAs and ROSAs) that can be integrated
within the relatively small physical envelopes defined by compact
components, such as a Host Bus Adapter ("HBA"). Embodiments of the
present invention can interoperate with a desktop computer, a
laptop computer, or other similar computer system, while
maintaining compliance with applicable operational and performance
standards.
As used herein, "OSA" refers to any one of a transmit optical
subassembly ("TOSA") or a receive optical subassembly ("ROSA").
Further, a "substrate" refers to a printed circuit board ("PCB")
having electrically conductive elements such as circuit traces for
transmitting power and/or communication signals between components
of a modular optical device and another system or device, such as a
computer system. A transceiver PCB (e.g., a Host Bus Adapter) can
include circuits, devices and systems for facilitating the
operation and control of the modular optical device. Such circuits,
devices and systems include, but are not limited to, a laser
driver, a post amplifier, and transimpedance amplifier.
Embodiments of the present invention include a dual stage
fabricated leadframe package (hereinafter referred to as a "dual
stage fabricated package") with digital diagnostics insert package.
The dual stage fabricated package includes a first fabricated
package and a second fabricated package. One or more first
leadframe portions can mechanically couple the first fabricated
package to the second fabricated package and electrically couple
components included in the first fabricated package to contacts
exposed in the second fabricated package. One or more second
leadframe portions can mechanically couple the second fabricated
package to the digital diagnostics insert package and electrically
couple contacts exposed in the second fabricated package to
contacts exposed in the digital diagnostics insert package.
Accordingly, components in the first, second, and digital
diagnostics insert packages can interoperate to implement digital
diagnostics functions.
The first fabricated package can include a light source (e.g.,
vertical cavity surface emitting laser ("VCSEL")) and/or light
detector (e.g., photodiode) as well as corresponding openings for
transmitting and receiving optical signals. The light source and
light detector can be wire bonded to portions of leadframes that
extend into the first fabricated package. This allows the light
source and light detector to be electrically connected to other
components, for example, in the second fabricated package and/or in
the digital diagnostics insert package, that are also connected to
the leadframes.
The second fabricated package includes exposed contacts for
electrically connecting to active and/or passive circuitry
components for driving the light source (e.g., a laser driver),
converting a received light signal (e.g., transimpedance
amplifier), or for implementing other optical signal processing.
Such other components can be component inserts accepted within the
second fabricated package. These other components can be, for
example, PCBs, ceramic substrates, silicon substrates, glass
substrates, and other leadframe-based (possibly insert-molded)
substrates that include packaged ICs, bare ICs, and/or passive SMT
components.
PCB or other component inserts accepted within the second
fabricated package can be wire bonded to contacts exposed at the
second fabricated package. Accordingly, circuitry components on a
PCB or other component insert can be electrically coupled (via the
one or more first leadframe portions) to the light source and/or
light detector. For example, a PCB or other component insert can
include die attached and/or wire bonded integrated circuits.
Integrated circuits of a component insert can be epoxy glob topped
or capped for protection. An assembled PCB or other component
insert can also include surface mount components. A PCB or other
component insert can be mechanically coupled to the second
fabricated package using an adhesive, such as, for example
epoxy.
The digital diagnostics insert package also includes exposed
contacts for electrically connecting to a diagnostic component
insert having active and/or passive circuitry for implementing
digital diagnostics functions, such as, for example, providing
(potentially real-time) diagnostic information about a
transceiver's operating conditions (power, current, voltage,
wavelength and temperature monitoring), generating diagnostic data
by digitizing analog transceiver signals, internally or externally
calibrating a transceiver, issuing alarms and warnings (e.g., based
on specified power, current, voltage, wavelength and temperature
thresholds), retrieving vendor information, and querying a
transceiver for supported features (encoding, bit rate, etc). Such
other components can be included on component inserts as previously
described. Circuitry components for implementing digital
diagnostics functions can include a processor for executing
instructions as well as Random Access Memory ("RAM") and/or
Read-Only Memory ("ROM") for storing and retrieving instructions
and data values. Exposed connections of a diagnostic component
insert can be wire bonded to contacts exposed within the digital
diagnostics insert package.
PCB or other component inserts accepted within the digital
diagnostics package can be wire bonded to contacts exposed at the
digital diagnostics package. Accordingly, circuitry components on
the diagnostic component insert can be electrically coupled (via
the one or more second leadframe portions) to the contacts exposed
at the second fabricated package. Component inserts accepted within
a digital diagnostics package can be mechanically coupled to the
digital diagnostics package, protected, and configured as
previously described
The digital diagnostics insert package can also include an external
connection, such as, for example, one or more third leadframe
portions in a thru hole pin or formed lead configuration, for
connecting (e.g., surface mounting) the dual stage fabricated
package with digital diagnostics insert package to a Printed
Circuit Board Assembly ("PCBA") or a Host Bus Adapter ("HBA"). When
active and/or passive circuitry is included on component inserts,
there is a reduced (and potentially no) need to duplicate such
circuitry on the PCBA. Accordingly, the size of an HBA can be
reduced.
Embodiments of the dual stage fabricated package with digital
diagnostics insert package can be mechanically coupled to a lens
block that includes receptacles for accepting one or more lens
pins. For example, a lens block can be configured to accept a
transmission lens pin, a reception lens pin, or a combination of
transmission lens pins and/or reception lens pins. Accepted lens
pins can be mechanically coupled to the lens block. Lens pins
mechanically coupled to the lens block can provide appropriate
receptacles for receiving external optical connections. Lens pins
can include lenses that focus optical signals.
Accordingly, a lens included in a (transmission) lens pin can
direct a generated optical signal from the dual stage fabricated
package with digital diagnostics insert package to an external
component (e.g., an optical cable). On the other hand, a lens
included in a (reception) lens pin can direct a received optical
signal from an external component to the dual stage fabricated
package with digital diagnostics insert package. For example, an
optical signal generated at a laser included in the first portion
of the dual stage fabricated package can be transferred through the
lens block, transferred through a lens in a corresponding
transmission lens pin, to a corresponding optical cable. Likewise,
an optical signal received from an optical cable can be transferred
through a lens in a corresponding reception lens pin, transferred
through the lens block, into a corresponding photodiode in the
first portion of the dual stage fabricated package.
A dual stage fabricated package with digital diagnostics insert
package, a lens block, and one or more lens pins can be passively
or actively aligned to optimize optical signal strength. Dual stage
fabricated packages, digital diagnostics insert packages, lens
blocks, and lens pins can be fabricated (e.g., molded, machined,
cast, etc.) from plastic, metal, or any other suitable material
that will allow for alignment of such components relative to one
another. A dual stage fabricated package, a digital diagnostics
insert package, a lens block, and one or more lens pins can be
mechanically coupled using a variety of coupling means, such as,
for example, adhesive, metal clips, staples, laser welding, barbed
pin, etc. Laser welding can be particularly advantageous when
components (e.g., a lens block and a portion of a dual stage
fabricated package with digital diagnostics insert package) are
made of similar plastic compounds. Accordingly, a modular optical
device, such as, for example, an OSA, can include, a dual stage
fabricated package, a digital diagnostics insert package, one or
more component inserts, a lens block, and one or more lens
pins.
FIG. 1A illustrates an example leadframe 101 including components
of an example dual stage fabricated package with digital
diagnostics insert package 104. As depicted, dual stage fabricated
package with digital diagnostics insert package 104 includes
fabricated package 116 and fabricated package 114 (the combination
being dual stage fabricated package) and fabricated package 112.
Fabricated package 116 and fabricated package 114 are mechanically
and electrically connected by leadframe portion 119. Similarly,
fabricated package 114 and fabricated package 112 are mechanically
and electrically connected by leadframe portion 117.
Fabricated package 116 further includes transmission opening 122
for transmitting generated optical signals. For example, VCSEL 151
(Vertical Cavity Surface Emitting Laser) can transmit optical
signals out of transmission opening 122. Fabricated package 116
also includes detector opening 124 for detecting received optical
signals. For example, photodiode 152 can detect optical signals
received at detector opening 124. Components included in fabricated
package 116 can be wire bonded to contacts of leadframe 101, for
example, to contacts of portion 119. Accordingly, a light source
and photo detector in fabricated package 116 can be electrically
coupled to circuitry in or connected to fabricated package 114.
Fabricated package 114 includes insert opening 118 that can accept
component inserts having Integrated Circuits ("ICs") or surface
mount components that include active and/or passive circuitry
(e.g., circuitry of a laser driver) A component insert can be wired
bonded to contacts of leadframe 101, for example, to the metal
contacts within insert opening 118. Component inserts can be
secured to fabricated package 114 with epoxy. ICs can be protected
by epoxy globbing, potting, by attaching a cover over insert
opening 118, or by incorporating a cover into a lens holding clip.
A component insert accepted at fabricated package 114 can include
active and/or passive circuitry components for driving a light
source (e.g., a laser driver), converting a received light signal
(e.g., transimpedance amplifier), or for implementing other optical
signal processing. For example, circuitry of a component insert can
interoperate with components (e.g., a laser or photo diode) in
fabricated package 116 (via leadframe portion 119) to send and/or
receive optical signals.
Fabricated package 112 includes insert opening 181 that can accept
component inserts having Integrated Circuits ("ICs") or surface
mount components that include active and/or passive circuitry.
Component inserts can be electrically and mechanically coupled to
fabricated package 112 and protected as previously described. A
component insert accepted at fabricated package 112 can include
active and/or passive circuitry components for performing
diagnostic functions or for implementing other optical signal
processing. For example, circuitry of a component insert can
interoperate with components (e.g., of other component inserts) in
fabricated package 114 (via leadframe portion 117) to implement
diagnostic functions. Thru other leadframe portions (e.g.,
leadframe portion 119) component inserts accepted at fabricated
package 112 can also interoperate with components in fabricated
package 116 to send and/or receive optical signals.
Fabricated package 112 can also be mechanically connected to a
portion of leadframe 101, for example, leadframe portion 113, that
provides mechanical and/or electrical connections to external
components. External connections can be, for example, thru hole,
gull-wing, hot bar style, etc. It may be that portion 113 is
connected (both electrically and mechanically) to a Printed Circuit
Board Assembly ("PCBA") or a Host Bus Adapter ("HBA"). For example,
portion 113 can be used to surface mount fabricated package 112 to
a PCBA. Accordingly, components included in fabricated package 116
can be electrical connected to components in fabricated package 114
(through portion 119), further electrically connected to components
in fabricated package 112 (through portion 117), and further
electrically connected to external components (through portion
113).
In some embodiments, a corrosive resistant coating is used to
protect components, such as, for example, VCSEL 151 and photodiode
152, in fabricated packages 112, 114, and 116. For example, a
diluted silicone mixture can be used to coat the components of
fabricated packages 112, 114, and 116.
FIG. 1B illustrates components of the example dual stage fabricated
package with digital diagnostics insert package 104 in a fully open
configuration relative to corresponding printed circuit board
inserts 191 and 196. The fully open configuration in FIG. 1B may
result from trimming dual stage fabricated package with digital
diagnostics insert package 104 from leadframe 101. For example,
tooling of a (computerized or otherwise automated) component
assembly system can be programmed to trim dual stage fabricated
package with digital diagnostics insert package 104 from leadframe
101.
Tooling of a (computerized or otherwise automated) component
assembly system can also be programmed to appropriately insert PCB
insert 191 into insert opening 118 (in the depicted orientation of
FIG. 1B the top side of fabricated package 114). Alignment features
192 and alignment slots 193 facilitate proper alignment of PCB
insert 191 during insertion into insert opening 118. After
insertion into insert opening 118, electrical contacts of PCB
insert 191 can be wire bonded to exposed contacts in insert opening
118 to cause circuitry of PCB insert 191 to be electrically coupled
(via portion 119) to components included in fabricated package 116.
Also after insertion into insert opening 118, epoxy can be used to
mechanically secure PCB insert 191 to fabricated package 114.
Tooling of a (computerized or otherwise automated) component
assembly system can also be programmed to appropriately insert PCB
insert 196 (e.g., a diagnostic PCB insert) into insert opening 121
(in the depicted orientation of FIG. 1B the bottom side of
fabricated package 112). Alignment features 194 and alignment slots
195 facilitate proper alignment of PCB insert 196 during insertion
into insert opening 121. After insertion into insert opening 121,
electrical contacts of PCB insert 196 can be wire bonded to exposed
contacts in insert opening 121 to cause circuitry of PCB insert 196
to be electrically coupled (via portion 117) to components included
in fabricated package 114. Also after insertion into opening 121,
epoxy can be used to mechanically secure PCB insert 196 to
fabricated package 112.
Further, it should be understood that additional PCB inserts can be
accepted into insert opening 182 (in the depicted orientation of
FIG. 1B the bottom side of fabricated package 114) and into insert
opening 181 (in the depicted orientation of FIG. 1B the top side of
fabricated package 112). These additional PCB inserts can be
secured and protected as previously described. For example,
alignment features 199 can facilitate proper insertion of a PCB
insert into insert opening 182. Likewise, alignment features 198
can facilitate proper insertion of a PCB insert into insert opening
181.
Additionally, although PCB inserts have been described, it should
be understood that insert openings 118, 121, 181, and 182 are not
limited to accepting PCB inserts. That is, other types of component
inserts, such as, for example, ceramic substrates, silicon
substrates, glass substrates, and other leadframe-based (possibly
insert-molded) substrates can also be accepted at any of insert
openings 118, 121, 181, and 182. For example, it may be that a
glass substrate is inserted into insert opening 118. Embodiments
also include insertion of different types of component inserts into
different insert openings. For example, a silicon substrate insert
(with appropriate alignment slots) can be accepted at insert
opening 118 and a ceramic substrate insert (with appropriate
alignment slots) can be accepted at insert opening 182 (or vice
versa). Tooling of a (computerized or otherwise automated)
component assembly system can be programmed to insert component
inserts into fabricated packages 112 and 114 where and when
appropriate.
Fabricated packages 112, 114, and 116 can be fabricated at the same
time thereby reducing the costs of manufacturing dual stage
fabricated package with digital diagnostics insert package 104.
Once assembled, dual stage fabricated package with digital
diagnostics insert package 104 is a low cost, reduced form factor
transceiver. For example, dual stage fabricated package with
digital diagnostics insert package 104 can be mechanically coupled
to other components to facilitate OSA functionality, for example,
as part of an optical transceiver.
FIG. 2A illustrates an example dual stage fabricated package with
digital diagnostics insert package 104 including corresponding
printed circuit boards 191 and 196 in a partially formed
configuration relative to lens block 103 and lens pins 108 and 106.
The partially formed configuration in FIG. 2A may result from
partially bending leadframe portions 119 and 117. For example,
tooling of a (computerized or otherwise automated) component
assembly system can be programmed to partially bend leadframe
portions 117 and 119 resulting in the partially formed
configuration of FIG. 2A.
Lens block 103 can include corresponding receptacles for accepting
lens pins. Each of the lens pins 108 and 106 can include a
corresponding lens element that facilitates the transfer
(transmission or reception) of optical signals. For example, lens
pin 108 can be positioned and aligned over transmission opening 122
such that generated optical signals (e.g., from VCSEL 151) are
transmitted out the end of lens pin 108. Similarly, lens pin 106
can be positioned and aligned over reception opening 124 such that
received optical signals are directed at a corresponding photo
detector (e.g., detected by photodiode 152).
A lens block may or may not include lens elements. For example, in
some embodiments, lens elements are included in appropriate
receptacles based on lens block configuration. In other
embodiments, no receptacles include lens elements.
In some embodiments, lens elements are included at various
different locations within a lens pin. For example, lens elements
can potentially be included at one or more lens element locations
in lens pins 106 and 108.
As previously described, components of a modular optical device can
be passively or actively aligned. Passive alignment can include
assembling components that were manufactured within specified
tolerances such that assembling the components causes the
components to be aligned. For example, passive alignment can
include obtaining a lens block including a transmitting lens pin
and a receiving lens pin, each of the lens pins being configured to
receive a fiber optic cable that is capable of carrying optical
signals. Passive alignment can also include obtaining a dual stage
fabricated package with insert digital diagnostics component that
includes a light emitting component and a light detecting
component. Passive alignment can also include passively aligning
the light emitting component with a lens in the transmitting
receptacle by attaching the lens block to the dual stage fabricated
package with insert digital diagnostics component such that a
specified optical power from the light emitting component through
the transmitting receptacle can be achieved.
Active alignment can include adjusting the position of components
that are lightly held together such that optical signal strength is
optimized and then more permanently fixing the position of the
components. For example, active alignment can include aligning a
lens pin, a lens block, and a dual stage fabricated package with
insert digital diagnostics component in a first direction, a second
direction, and a third direction such that the signal strength of
optical signals transferred between a lens included in the lens pin
and the dual stage fabricated package is optimized. Active
alignment can also include mechanically coupling the lens pin to
the lens block to fix the position of the lens pin relative to the
dual stage fabricated package in the first direction. Active
alignment can also include subsequent to mechanically coupling the
lens pin to the lens block, re-aligning the lens block and the dual
stage fabricated package in the second and third directions such
that the signal strength of optical signals transferred between the
lens pin and the dual stage fabricated package is again optimized.
Active alignment can also include mechanically coupling the lens
block to the dual stage fabricated package to fix the position of
the lens block relative to the dual stage fabricated package in the
second and third directions.
In some embodiments, optimizing signal strength includes aligning
components such that the output signal strength is maximized. In
other embodiments, optimizing signal strength includes aligning
components such that the output signal strength closely
approximates a pre-selected signal strength (e.g., that is some
amount less than the maximum possible output signal strength).
Optimizing signal strength to a pre-selected level can include
determining the alignment that maximizes signal strength and then
"backing off" from the maximum by a fixed amount in a controlled
manner.
Generally, dual stage fabricated package with digital diagnostics
insert package 104 and other corresponding components can be used
in modular optical devices of various form factors, including, but
not limited to, an SFF, SFP, and XFP optical transceiver.
Accordingly, digital diagnostics functionality can be implemented
in relatively small form factor devices. The foregoing are
exemplary however, and modular optical devices can be implemented
in various other smaller form factor devices well. Further,
embodiments of the invention are suitable for use in connection
with a variety of data rates such as about 1 Gbps, about 2 Gbps,
about 4 Gbps, and about 10 Gbps, or higher.
FIG. 2B illustrates an example of an assembled modular optical
device 150 including dual stage fabricated package with digital
diagnostics insert package 104. As depicted, lens pins 106 and 108
are mechanically coupled to lens block 103. Lens block 103 is in
turn mechanically coupled to fabricated package 116.
FIG. 2C illustrates an example of an assembled modular optical
device 150 including dual stage fabricated package with digital
diagnostics insert package 104 in a fully formed configuration. As
depicted in FIG. 2C, leadframe 117 is completely bent.
Modular optical device 150 can be positioned on a printed circuit
board assembly or other substrate. Leadframe portion 113 can
facilitate electrical communication between circuitry on the
substrate (or other components to which the modular optical device
is attached) and modular optical device 150. Accordingly, leadframe
portion 113 enables data transmission and/or data reception, as
well as the transmission and reception of control and monitoring
signals, between modular optical device and the substrate (or other
appropriate components). Electrical communication can include
communication between a light source included in fabricated package
116, such as, for example, VCSEL 151 and other circuitry on the
substrate. Likewise, electrical communication can include
communication between a light detector, such as, for example,
photodiode 152, included in fabricated package 116 and other
circuitry on the substrate. Similarly, electrical communication can
include communication between circuitry of PCB inserts 191 and 196
(as well as other component inserts) and circuitry on the
substrate.
Leadframe portion 113 can be connected to the substrate in a
variety of ways, including, but not limited to, surface mount
connectors, thru hole connectors, and compression-type connectors.
A connected substrate can include an edge connector suitable for
connecting the substrate to a corresponding receptacle in a
computer system, for example, to establish a mechanical and
electrical interface between the substrate and computer system bus.
Alternately, the edge connector can facilitate establishment of a
mechanical and electrical interface between modular optical device
150 and a variety of other devices, such as, for example, an
optical router or optical hub.
Components (not shown), such as, for example, light emitting
diodes, a laser driver, a post amplifier, a transimpedance
amplifier, a current bias driver, volatile and/or non-volatile
memory, and a thermo-electric cooler ("TEC") can be implemented on
a transceiver PCBA or substrate. Components can be implemented on
either side of the transceiver PCBA or substrate as appropriate.
Components on a substrate can interface electrically with the
modular optical device through leadframe portion 113. Components on
a PCB insert can interface electrically with a substrate through
leadframe portion 113 and with components in other fabricated
packages through corresponding leadframe portions 117 and 119.
When the substrate is coupled to a computer system or other device,
such implemented components can interface electrically with the
computer system or other device. Mounting components, circuits and
devices on both sides of the substrate or transceiver PCBA can
facilitate a compact structure without any meaningfull loss in
functionality. Moreover, as previously described, this aids space
conservation on an HBA or other device to which the modular optical
device is mounted.
The modular optical device 150 can be arranged on a substrate such
that distance between lens pins 108 and 106 is sufficiently large
such that a first optical connector can be connected to lens pin
106, while a second optical connector is simultaneously connected
to lens pin 108 and vice versa. Generally, lens pins 106 and 108
can be configured to receive any of a variety of connectors, such
as, for example, SC, LC, ST, and FC connectors. Other
configurations of modular optical devices can be configured as
appropriate to simultaneously connect to a corresponding number of
optical connectors.
Generally, a HBA can be any type of printed circuit board
implemented as a suitable connector interface for use with a
computer system, wherein the connector interface may take the form
of, for example, a peripheral component interconnect ("PCI") card
having edge connectors configured and arranged to interface with a
desktop computer system. The connector interface may alternatively
take the form of, for example, a printed circuit board with a
serial or parallel port, or a Personal Computer Memory Card
International Association ("PCMCIA") standard card. Note that as
used herein, "connector interface" generally refers to a PCB or
other device that acts as an interface between an optical
component, such as the modular optical device, and a host system
such as a laptop computer, desktop computer, or portable computing
systems such as personal digital assistants ("PDAs").
Referring now to FIG. 3A, FIG. 3A illustrates an example side view
of an assembled dual stage modular optical device 150 with
leadframe 113 in a thru hole pin configuration. Modular optical
device 150 includes fabricated package 112, fabricated package 114,
fabricated package 116, leadframe portion 119, leadframe portion
117, lens block 103, lens pin 106, and lens pin 108 (which from the
side view perspective in FIG. 3A is behind lens pin 106 and thus is
not visible). Further, modular optical device 150 includes a thru
hole pin configured leadframe 113, which can be an array of
electrical pins suitable for connecting to substrate 301. Although
not visible, printed circuit board insert 191 is contained in
fabricated package 114 and printed circuit board insert 196 is
contained in fabricated package 112. As depicted in FIG. 3A,
substrate 301 has length 302.
Stand-offs 128 and 138 mechanically secure optical device 150 to
substrate 301 and elevate modular optical device 150 so that
leadframe portion 119 is not in direct contact with substrate 301.
Stand-offs 128 and 138 can be separate pieces or can be integral
features of lens block 103 and fabricated package 114 respectively.
The relative size and position of stand-offs are approximate and
can be varied based on package configuration.
As depicted in FIG. 3A, the thru hole pin configuration of
leadframe 113 facilitates electrical communication between
circuitry (not shown) on substrate 301 (or other components to
which modular optical device 150 is mounted) and fabricated package
112, such as, for example, circuitry on PCB insert 196. To secure
modular optical device 150 to substrate 301, pins of the thru hole
pin configured leadframe 113 (e.g., thru hole pin 133 and other
pins) can be inserted through thru holes (e.g., thru hole 123 and
other thru holes) in substrate 301. Subsequently, thru hole pins
can be mechanically and electrically coupled to substrate 301.
Accordingly, a thru hole pin configured leadframe enables data
transmission and/or reception, as well as the transmission and
reception of control and monitoring signals, between fabricated
package 112 and substrate 301 (or other appropriate
components).
FIG. 3B illustrates an example side view of an alternate
configuration of dual stage modular optical device 151 positioned
on substrate 311 that facilitates electrical communication between
circuitry on substrate 311 (or other components to which modular
optical device 151 is mounted) and fabricated package 112. In the
embodiment of FIG. 3B, stand-offs 128 and 138 mechanically secure
optical device 151 to substrate 311 and elevate modular optical
device 151 so that leadframe portion 119 is not in direct contact
with substrate 311. The relative size and position of stand-offs
are approximate and can be varied based on package configuration.
SMT (Surface Mount Technology) formed leadframe 191 electrically
connects components of fabricated package 112 to components of
substrate 311. As depicted in FIG. 3B, substrate 311 has length 303
similar to length 302.
FIG. 3C illustrates an example side view of another alternate
configuration of modular optical device 152 positioned on substrate
321 that facilitates electrical communication between circuitry on
a substrate 321 (or other components to which modular optical
device 152 is mounted) and fabricated package 112. Formed leadframe
121 mechanically and electrically couples optical device 152 to
substrate 321. The configuration of formed leadframe 121 along with
the mounting point being on the underside of substrate 321, results
in height 120 being reduced as compared to other configurations
(e.g., those in FIGS. 3A and 3B). Further as depicted in FIG. 3C,
length 304 is substantially reduced compared to lengths 302 and
303. An external support device, such as, for example, a mounting
bracket can, be used to support modular optical device 152 in
use.
As depicted in FIGS. 3A, 3B, and 3C, fabricated packages 112 and
114 are of essentially the same size and same configuration and
leadframe portion 117 is in a completely bent configuration.
However, it should be understood that fabricated package 112 can be
of a different size and different configuration than fabricated
package 114. For example, it may be that to accommodate additional
components, fabricated package 112 is somewhat longer than
fabricated package 114. To maintain a constant cross-sectional area
leadframe portion 117 can be bent to some intermediate extent.
In some alternate mounting configurations, leadframe portion 117 is
also bent to some intermediate extent. For example, when the plane
of a substrate is in close proximity to the plane formed by the OSA
optical axes, leadframe portion 117 may be bent to some
intermediate extent. Bending leadframe portion 117 to an
intermediate extent advantageously facilitates minimizing the
length of leadframe portion 113.
Embodiments of the present invention have been described with
respect to three separate fabricated packages (e.g., packages 116,
114, and 112). However, it would be apparent to one skilled in the
art, after having reviewed this description, that embodiments of
the present invention can include less than or more than three
separate fabricated packages.
For example, it may be that a lead frame includes two fabricated
packages. A first package may be similar to fabricated package 116
and a second package may be similar to fabricated package 114.
Alternately, the second package can be of some other size and/or
shape. A digital diagnostics component insert can be inserted into
an insert opening (e.g., similar to insert opening 182) of the
second fabricated package to implement digital diagnostics
functions similar to those previously described. Another component
insert (e.g., including a laser driver and/or transimpedance
amplifier) can be inserted into another insert opening (e.g.,
similar to insert opening 118) to implement other processing as
previously described
It may also be that a lead frame includes four or more fabricated
packages. At least one package can be configured similar to
fabricated package 116. Other packages can be configured similar to
either of packages 114 and 112 or can be of other sizes and shapes.
A digital diagnostics component insert can be inserted into an
insert opening (e.g., similar to insert opening 181) of one of the
other packages to implement digital diagnostics functions similar
to those previously described. Other packages can accept component
inserts for other purposes, such as, for example, consolidating
transmitter and receiver physical layer functions in a SerDes
(serialization/deserialization) IC, signal conditioning using a CDR
(clock and data recovery) IC, and adaptively compensating using an
EDC (electronic dispersion compensation) IC. Packages can be
connected to one another via leadframe portions.
The present invention may be embodied in other specific forms
without departing from its spirit or essential characteristics. The
described embodiments are to be considered in all respects only as
illustrative and not restrictive. The scope of the invention is,
therefore, indicated by the appended claims rather than by the
foregoing description. All changes, which come within the meaning
and range of equivalency of the claims, are to be (embraced within
their scope.
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